In R, objects can be of different class such as vector, list, dataframe, ts, etc. When you load a dataset into R, it may not necessarily be a time series object. We can use the
is.ts() function to test if the given object is a time series (ts) object or not.
Below we perform this test on all the objects we’ve created so far in this course.
> is.ts(msft_ts)  TRUE > is.ts(GDP_data)  TRUE > is.ts(sp_vector)  FALSE > is.ts(sp_ts)  TRUE >
As you can see, all objects return TRUE except
sp_vector which is a vector.